High pressure and high temperature refrigerant vapor compressor



July 5, 1966 REFRIGERANT VAPOR COMPRES SOR 5 Sheets-Sheet 1 Filed Nov. 18, 1963 ,wlw. l. w V w/ l fi ww 3M w 3 @R Q mm & rd a a Z m h w m ATTORNEY July 5, 1966 J. o. PORTEOUS HIGH PRESSURE AND HIGH TEMPERATURE REFRIGERANT VAPOR COMPRESSOR 5 Sheets-Sheet 2 Filed NOV. 18, 1963 5/ INVENTOR 0M ATTORNEY JOHN O PORTEOUS W f u 5 W0 fi f :2 LEE: E 4 8 a 6 9 w I Tm 5 July 5, 1966 J o. PORTEOUS HIGH PRESSURE AND HIGH TEMPERATURE REFRIGERANT VAPOR COMPRESSOR Filed Nov. 18 1963 3 Sheets-Sheet 5 INVENTOR. JOHN OPORTEOUS ATTORNEY United States Patent G 3,259,306 HIGH PRESSURE AND HIGH TEMPERATURE REFRIGERANT VAPOR COMPRESSOR John 0. Porteous, Pasadena, Calif, assignor of one-half to David F. Thomas, Altadena, Calif. Filed Nov. 18, 1963, Ser. No. 324,364 7 Claims. (Cl. 230-147) My invention relates generally to fluid displacement mechanisms such as pumps, compressors and similar machines.

The primary object of my invention is to provide a pumping mechanism structurally characterized by means enabling refrigerant in a vaporous state at an extremely low absolute pressure such as 1.5 lbs. As an example, to be compressed to an extremely high absolute pressure such as 267 lbs., also as an example, during normal operation in accordance with conventional refrigerating practice and with the refrigerant remaining in a vaporous state at approximately 250 degrees Fahrenheit discharge temperature for the removal of heat therefrom externally of the mechanism.

Another object of my invention is to provide a high pressure and temperature vapor compressor which is the functional equivalent of a two-stage reciprocating pump, and is particularly adapted for the compressing of the most modern high pressure refrigerant to prevent reexpansion with the attendant heating of refrigerant vapor, all with maximum efiiciency and minimum consumption of power.

A further object of my invention is to provide a fluid displacement mechanism which specifically includes a piston having a plurality of peripheral working surfaces and carrying vanes co-acting with stator elements to form a plurality of working chambers under the action of a cam imparting an eccentric motion to the piston upon rotation of the operating shaft of the mechanism while the piston is restricted by a novel arrangement of link mechanism involving negligible friction, to an oscillatory motion during rotation of the shaft in order for the piston to co-act with the working chambers in admitting, compressing and exhausting the refrigerant vapor therefrom with maximum efficiency.

Still another object of my invention is to provide a fluid displacement mechanism as above described in which the exhaust ports of the working chambers are arranged and formed in a novel manner insuring complete removal of all compressed vapor from the chambers at the completion of the compressing action, upon which the exhaust ports are closed fiuid-tight from the working chambers by an end Wall of the piston and by outwardly-opening valves to positively prevent valve lag.

A still further object of my invention is to provide a fluid displacement mechanism as above set forth in which the vanes carried by the stator elements have sealing members of novel construction and correlated with the vanes to bear against and automatically conform to the contour of the peripheral working surfaces of the piston during its eccentric and oscillating movements and in a manner to distribute over a relatively large area the frictional load to which the sealing members are subjected by the heavy spring pressure necessarily imposed upon the vanes to confine the high pressure refrigerant vapor against leakage from the working chambers, whereby to materially contribute to the high pumping efficiency of the mechanism.

Another object of my invention is to provide as an integral part of the fluid displacement mechanism a lubricant circulating system arranged in a novel manner to deliver lubricant to the peripheral working surfaces of the piston exteriorly of the working chambers and adjacent to the sealing members of the vanes so as to effectively provide positive lubrication for the sealing members while maintaining the working chambers free of lubricant for maximum vapor compressing e-fiiciency.

With these and other objects in view, my invention resides in the combinations, arrangements and functional relationships of elements as set forth in the following specification and particularly pointed out in the appended claims.

In the accompanying drawings,

FIGURE 1 is a longitudinal, axial sectional view of one form of high pressure and temperature refrigerant vapor compressor embodying my invention, taken on the line 11 of FIGURE 2 and looking in the direction of the arrows;

FIGURE 2 is a vertical, transverse sectional view taken on the line 2-2 of FIGURE 1 and looking in the direction of the arrows;

FIGURES 3 and 4 are fragmentary sectional views similar to FIGURE 2 and illustrating successive positions of the working parts of the compressor during a cycle of operation;

FIGURE 5 is a vertical, transverse sectional view taken on the line 5-5 of FIGURE 1 and looking in the direction of the arrows;

FIGURE 6 is a fragmentary detail sectional view taken on the line 6-6 of FIGURE 5;

FIGURE 7 is a vertical, transverse sectional view taken on the line 7-7 of FIGURE 2;

FIGURE 8 is a fragmentary detail sectional view taken on the line 88 of FIGURE 2; and

FIGURE 9 is an enlarged fragmentary detail sectional view taken on the line 9-9 of FIGURE 8.

Referring specifically to the drawings, my invention in its illustrated embodiment comprises a housing H composed of a support 10 and a deep cup-shaped cover 11. The support 10 is in the form of circular heads 12 and 13 spaced apart and rigidly connected in parallelism by a centrally located tubular portion 14 and by radially extending webs 15. The portion 14 is surrounded by an annular low pressure chamber 16 having an inlet 17 (FIG- URE 7) adapted for connection to the low pressure side of a refrigerant circulating system (not shown). The cover 11 is rigidly secured to the head 12 by cap screws 18 and co-acts therewith to form a high pressure chamber 19 having an outlet 20 controlled by a standard refrigerating shutoff or service valve (not shown) connected to the high pressure side of the refrigerating system.

Stator elements 25 and 25a of identical construction are provided at one end with flanges 26 and 26a respectively, through which pass cap screws 27 and 27a threaded into the head 12 to rigidly secure the elements to the latter. The stator elements are provided at the other end with similar flanges 28 and 28a respectively, into which cap screws 29 and 2% are threaded to secure them to a supporting member in the form of a circular head 3t).

An operating or drive shaft is journaled in a bearing 36 supported in a recess 37 in the head 13, and may constitute the armature shaft of an electric motor whose casing 38 is secured to the head 13 by cap screws 39 so as to rigidly connect the motor and the compressor housing H to form a unitary structure. The opposite end of the shaft 35 is reduced in diameter 40 and journaled in a bearing 41 in the head 30 so as to co-act with the bearing 36 in mounting the shaft for rotation about a fixed axis. The portion of the length of the shaft 35 spanning the space between the heads 12 and 30 is constructed to provide a cam 42 in the form of an eccentric on which is mounted by means of needle bearings 43 and 44 a piston 45 of generally cylindrical form having a working fit between the heads 12 and 30 and provided at diametrically opposed locations with segmental, peripheral working surfaces 46 and 46a.

The stator elements and 25a which are of segmental form, are diametrically opposed and are provided with internal, arcuate working surfaces 47 and 47a, respectively, whose common center is coincident with the axis of the shaft 35. The stator surfaces 47, 47a co-act with the respective piston surfaces 46, 46a to form work ing chambers 56 and 50a between vanes 51, 51 and 51a, 51a carried by the respective stator elements and coextensive in length with the piston 45. The vanes 51, 51a are reciprocably mounted in slots 52, 52a in the respective stator elements and are provided with pockets 53, 53a to receive coil springs 54, 54a urging the vanes towards the periphery of the piston 45. The inner ends of the vanes 51, 51a are provided with arcuate recesses 55, 55a respectively, which form seats for the complementarily shaped surfaces of sealing members or shoes 56, 56a coextensive in length with the piston 45.

The shoes 56, 56a have arcuate faces 57, 57a conforming to and riding upon the peripheral working surfaces 46, 460 respectively, so as to distribute over a relatively large area the frictional load resulting from the heavy spring pressure necessarily imposed upon the vanes 51, 51a to confine the high pressure refrigerant vapor against leakage from the working chambers 59 and Sila. Each of the shoes '56, 56a is provided with a fixed pin 60 (FIGURES 8 and 9) having a shank 61 passing through an arcuate slot 62 in the respective vanes 51, 51a and having a head 63 to definitely limit oscillation of the shoe relative to the vane to that necessary in the operation of the compressor and to thus prevent malfunctioning of the shoe.

Breathing vents 64 (FIGURE 5) extend through the head 30 (FIGURE 8) into the slots 52, 52a of the stator elements 25, 25a to compensate for reciprocating movement of the vanes in the slots. The lower two vents 64 are protected against the entrance of lubricating oil by splash guards 64a.

Rigidly secured to the piston 45 by cap screws 66 is a bracket 67 having spaced cars 68 receiving therebetween one end of a link 69 to which is fixed a pin 70 journaled in needle bearings 71 in the cars 68. A pin 72 is fixed in the other end of the link 69 and is journaled in needle bearings 73 in the bifurcated end of a second link 74, the other end of which extends between ears 75 of a pin 76 and has fixed thereto a pin 77 journaled in needle bearings 78 in the cars 75. The pin 76 constitutes a fixed pivot anchor member mounted in needle bearings 79 supported in a recess 80 in the head 12 and is confined against axial displacement from the recess by a spring ring 81.

The mounting of the anchor pin 76 is upon an axis parallel to and sufiiciently offset laterally from the axis of the drive shaft 35 for the links 69 and 74 to co-act in restricting movement of the piston on the cam 42 to a predetermined angle of oscillation as the shaft rotates, with negligible friction being introduced by this specific mechanism.

Intake ports 35 and a through the head 12 place the low pressure chamber 16 in communication with the respective working chambers 50 and Sila, whereas exhaust ports 86 and 86a through the head 30 place the respective working chambers in communication with the high pressure chamber 19. It will be noted that the intake ports 85, 85a are in the form of arcuate slots located approximately midway between the respective vanes 51 and 51a so .as to be controlled by one end wall 45a of the piston 45. The exhaust ports 86, 86a are located at one of the vanes and are controlled by the other end Wall 4512 of the piston. The exhaust ports 86, 86a are shaped to terminate in sharp corners 87, 87a (FIGURE 5) flush with the working surfaces 47, 47a of the respective stator elements 25 and 25a for a purpose to be later described. Outwardly opening check valves 88 and 88a mounted on the head 31) are spring-urged to close the respective exhaust ports 86 and 86a.

The reduced end 40 of the drive shaft 35 which passes through the body 90 and cover 91 of an oil pump P, has

fixed thereto a counterweight 92 to compensate for the eccentrically disposed mass of the piston 45. The body 96 is secured to the head 30 by cap screws 93, and the cover 91 is secured to the body by screws 94 for co-action with the body in enclosing meshing gears 95 and 96, the former of which is keyed to the shaft 35 so as to be driven thereby, whereas the gear 96 is rotatably mounted on a stub shaft 97 fixed in the body. A suction tube 93 (FIG- URE 5) extends from the body 90 into a reservoir of oil in the bottom portion of the chamber 19, whereas discharge tubes 99 and 10th extend from the body through the head 36 to a location above and between the stator elements 25 and 25a as indicated in phantom lines in FIGURE 2 and in broken lines in FIGURE 5. The tubes 99 and 1M deliver oil to the working surfaces 46, 46a of the piston 45 exteriorly of the working chambers 50 and 56a for circulation of the oil as indicated by the broken arrows in FIGURE 2. Oil from the pump P is also delivered through suitable passages 101 in the shaft 35 to the shaft and piston hearings to insure positive lubrication thereof in the operation of the invention which is as follows:

Let it be assumed that the inlet 17 and outlet 20 are connected to the low and high pressure sides, respectively, of a refrigerating system for compressing and circulating a refrigerant which is maintained in a vaporous state during its flow through the vapor compressor, it being intended that the heat is to be removed from the refrigerant exteriorly of the compressor so that the latter operates at all times on a vaporous agent.

As the cycle of operation of the two working chambers 50 and 50a is identical and takes place successively at each degrees of travel of the drive shaft 35 in a counterclockwise direction as viewed in FIGURES 2, 3 and 4, a description of the operation in its relation to the working chamber 50 will suffice for both. With the working parts in the position shown in FIGURE 2, the intake port 85 is closed by the end wall 45a of the piston 45 so that as the piston is advanced by approximately 90 degrees rotation of the shaft 35 to the position shown in FIGURE 3, a partial vacuum will be created in the working chamber 50 as the working surface 46 of the piston moves away from the working surface 47 of the stator 25.

During the following 180 degrees of rotation of the shaft 35 which takes place from the position of the piston 45 shown in FIGURE 3 to that shown in FIGURE 4, the intake port 85 will be opened by the end wall 45a of the piston 45 and will remain open so as to admit refrigerant vapor from the low pressure chamber 16 to the working chamber 56. During this movement the exhaust port 86 will be gradually opened by the end wall 45b of the piston until in the position shown in FIGURE 4 the intake port 85 is again being closed by the piston whereas the exhaust port is fully opened.

During the next 90 degrees of rotation of the shaft 35 to complete one revolution thereof, the charge of refrigerant vapor in the working chamber 50 will be compressed by the piston and forced through the exhaust port' 86 past the check valve 88 into the high pressure chamber 19 with maximum etficiency due to the specific shape of the exhaust port 86 with its corner 87 flush with the working surface 47 of the stator 25. It will be noted that during this cycle of operation the shoes 56 will oscillate upon the arcuate seats 55 in the ends of the vanes 51 while the arcuate faces 57 of the shoes will ride upon the working surface 46 of the piston. By the provision of the shoes 56 and the manner in which they are interposed between the vanes and piston, the working chamber is positively sealed fluid-tight by the vanes under the heavy spring pressure necessary to confine the high pressure refrigerant vapor against leakage, all while distributing the frictional load imposed by the springs 54 over a rela tively large bearing area.

It will be noted that the link mechanism composed of the pivotally connected links 69 and 74 pivotally connected to the piston 45 and to the fixed pivot anchor member 76 restricts the piston to an oscillating movement upon the cam 42 within a precalculated angle as the piston is moved by the cam in an orbital path about the axis of the shaft 35', all of which is accomplished with but negligible friction being introduced by this link mechanism. Furthermore, it will be clear that as the exhaust ports 86, 86a are controlled at the inner side of the head 30 by the end wall 45b of the piston 45 and at the outer side of the head by the check valves 88, 88a, respectively, valve lag with its attendant decrease in efficiency is positively prevented so as to insure maximum compression of the charges of refrigerant vapor in the Working chambers 50 and 50a by the co-action of the piston and stator elements.

I claim:

1. In a high pressure and temperature refrigerant vapor compressor, a housing defining a high pressure chamber having an outlet adapted for connection to the high pressure side of a refrigerant circulating system and provided with a head; a second head in said chamber; a plurality of segmental stator elements between said heads having internal arcuate working surfaces; means rigidly securing the stator elements to the heads a predetermined angular distance apart; a rotatably mounted drive shaft in said housing having a cam between said heads eccentrically related to the shaft axis; a piston mounted on said cam having peripheral working surfaces; vanes slid- I ably mounted in said stator elements and spring-urged into engagement with said working surfaces of the piston for co-action therewith and with said working surfaces of the stator elements in defining working chambers; means co-acting with the piston to prevent its rotation and compelling oscillation of the piston through a predetermined angular distance when the piston is driven by the cam; the first said head having intake ports adapted for connection to the low pressure side of the refrigerant circulating system and communicating with said working chambers so as to be controlled by an end wall of the piston; the second said head having exhaust ports communicating with said high pressure chamber and with said working chambers so as to be controlled by the other end wall of the piston; said intake and exhaust ports being located in the working chambers for the piston to co-act therewith in creating a partial vacuum therein, then admitting refrigerant to the working chambers, followed by compression of the refrigerant and its discharge from the working chambers; and means co-acting with the exhaust ports to enable the compressed refrigerant to be pumped into the high pressure chamber.

2. In a high pressure and temperature refrigerant vapor compressor, a housing defining a high pressure chamber having an outlet adapted for connection to the high pressure side of a refrigerant circulating system and provided with a head; a second head in said chamber; a

plurality of segmental stator elements between said heads having internal arcuate working surfaces; means rigidly securing the stator elements to the heads a predetermined angular distance apart; a rotatably mounted drive shaft in. said housing having a cam between said heads eccentrically related to the shaft axis; a piston mounted on said cam having peripheral working surfaces; vanes slidably mounted in said stator elements and spring-urged into engagement with said working surfaces of the piston for co-action therewith and with said working surfaces of the stator elements in defining working chambers; means co-acting with the piston to prevent its rotation and compelling oscillation of the piston through a predetermined angular distance when the piston is driven by the cam; the first said head having intake ports adapted for connection to the low pressure side of the refrigerant circulating system and communicating with the working chambers so as to be controlled by an end wall of the piston; the second said head having exhaust ports communicating with said high pressure chambers and with said working chambers so as to be controlled by the other end wall of the piston; said intake and exhaust ports being located in the working chambers for the piston to co-act therewith in inducing a partial vacuum therein, then admitting refrigerant to the working cha-mbers, followed by compression of the refrigerant and its discharge from the working chambers; and. outwardly opening check valves controlling the discharge of compressed refrigerant from the exhaust ports; the exhaust ports being shaped to co-act with the respective end wall .of the piston in enabling complete discharge of compressed refrigerant from the working chambers to be effected so as to prevent valve lag.

3. In a high pressure and temperature refrigerant vapor compressor, a housing defining a high pressure chamber having an outlet adapted for connection to the high pressure side of a refrigerant circulating system and provided with a head; a second head in said chamber; a plurality of segmental stator elements between said heads having internal arcuate working surfaces; means rigidly securing the stator elements to the heads a predetermined angular distance apart; a rotatably mounted drive shaft in said housing having a cam between said heads eccentrically related to the shaft axis; a piston mounted on said cam having peripheral working surfaces; vanes slidably mounted in said stator elements and spring-urged into engagement with said working surfaces of the piston for co-action therewith and with said working surfaces of the stator elements in defining working chambers; an anchor member; means pivotally mounting said member about a fixed axis parallel to and offset laterally from the axis of said shaft; a link pivotally connected to said anchor member; and a second link pivotally connected to the first said link and to the piston so as to prevent its rotation and compel its oscillation through a predetermined angle when the piston is driven by the cam; the first said head having intake ports adapted for connection to the low pressure side of the refrigerant circulating system and communicating with said working chambers so as to be controlled by an end wall of the piston; the second said head having exhaust ports communicating with said high pressure chamber and with said working chambers so as to be controlled by the other end wall of the piston; said intake and exhaust ports being located in the working chambers for the piston to co-act therewith inducing a partial vacuum therein, then admitting refrigerant to the working chambers, followed by compression of the refrigerant and its discharge from the working chambers; and means co-aeting with the exhaust ports to enable the compressed refrigerant to be pumped into the high pressure chamber.

4. In a high pressure and temperature refrigerant vapor compressor, a housing defining a high pressure chamber having an outlet adapted for connection to the high pressure side of a refrigerant circulating system and provided with a head; a second head in said chamber; a plurality of segmental stator elements between said heads having internal arcuate working surfaces; means rigidly securing the stator elements to the heads a predetermined angular distance apart; a rotatably mounted drive shaft in said housing having a cam between said heads eccentrically related to the shaft axis; a piston mounted on said cam having peripheral working surfaces; spring-urged vanes slidably mounted in said stator elements for co-action with said working surfaces of the piston and stator elements in defining working chambers; said vanes having seats; sealing members free to oscillate on said seats and having working faces in fluid-sealing engagement with said working surfaces of the piston; means co-acting with the piston to prevent its rotation and compelling oscillation of the piston through a predetermined angular distance when the piston is driven by the cam; the first said head having intake ports adapted for connection to the low pressure side of the refrigerant circulating system and communicating with said working chambers so as to be controlled by an end wall of the piston; the second said head havvhaving peripheral working surfaces; vanes ing exhaust ports communicating with said high pressure chamber and with said working chambers so as to be controlled by the other end wall of the piston; said intake and exhaust ports being located in the working chamber for the piston to co-act therewith in creating a partial vacuum therein, then admitting refrigerant to the working chambers, followed by compression of the refrigerant and its discharge from the working chambers; and means co-acting with the exhaust portsto enable the compressed refrigerant to be pumped into the high pressure chamber.

5. In a high pressure and temperature refrigerant vapor compressor, a housing defining a high pressure chamber having an outlet adapted for connection to the high pressure side of a refrigerant circulating system and provided with a head; a second head in said chamber; a plurality of segmental stator elements between said heads having internal arcuate working surfaces; means rigidly securing the stator elements to the heads a predetermined angular distance apart; a rotatably mounted drive shaft in said housing having a cam between said heads eccentrically related to the shaft axis; a piston mounted on said cam having peripheral working surfaces; spring-urged vanes slidably mounted in said stator elements for co-action with said working surfaces of the piston and stator elements in defining working chambers; said vanes having recesses defining arcuate seats; shoes having surfaces complementary to said recesses mounting the shoes therein for oscillatory movement; said shoes having working faces conforming to the peripheral working surfaces of the piston in fluid-sealing engagement therewith; means co-acting with the vanes and shoes to limit oscillatory movement of the shoes to prevent malfunctioning of the shoes; means co-acting with the piston to prevent its rotation and to compel oscillation of the piston through a predetermined angular distance when the piston is driven by the cam; the first said head having intake ports adapted for connection to the low pressure side of the refrigerant circulating system and communicating with said working chambers so as to be controlled by an end wall of the piston; the second said head having exhaust ports communicating with said high pressure chamber and with said working chambers so as to be controlled by the other end wall of the piston; said intake and exhaust ports being located in the working chambers for the piston to co-act therewith in creating a partial vacuum therein, then admitting refrigerant to the working chambers followed by compression of the refrigerant and its discharge from the working chambers; and means co-acting with the exhaust ports to enable the compressed refrigerant to be pumped into the high pressure chamber.

6. In a high pressure and temperature refrigerant vapor compressor, a housing defining a high pressure chamber having an outlet adapted for connection to the high pressure side of a refrigerant circulating system and provided with a head; a second head in said chamber; a plurality of segmental stator elements between said heads having internal arcuate working surfaces; means rigidly securing the stator elements to the heads a predetermined angular distance apart; a rotatably mounted drive shaft in said housing having a cam between said heads eccentrically related to the shaft axis; a piston mounted on said cam slidably mounted in said stator elements and spring-urged into engagement with said working surfaces of the piston for coaaction therewith and with said Working surfaces of the stator elements in defining working chambers; means co- .acting with the piston to prevent its rotation and to compel oscillation of the piston through a predetermined angular distance when the piston is driven by the cam; the first said head having intake ports adapted for connection to the low pressure side of the refrigerant circulating system and communicating with said working cham- ,bers so as to be controlled by an end wall of the piston; the

second said head having exhaust ports communicating with said high pressure chamber and with said working chambers so as to be controlled by the other end wall of the piston; said intake and exhaust ports being located in the work-ing chambers for the piston to co-act therewith in creating a partial vacuum therein, then admitting refrigerant to the working chambers, followed by compression of the refrigerant and its discharge from the working chambers; means co-acting With the exhaust ports to enable the compressed refrigerant to be pumped into the high pressure chamber; and a lubricant circulating pump mounted on the second said head and operatively connected to said drive shaft to be driven thereby; said pump having a suction conduit through which lubricant is drawn from a reservoir in said high pressure chamber; said pump having discharge conduits passing through the second said head to a location from which lubricant is delivered to said working surfaces of said piston exteriorly of the working chambers so as to lubricate the shoes and drain into the reservoir.

7. In a high pressure and temperature refrigerant vapor compressor, a support having a plurality of spaced heads and a low pressure chamber between the heads provided with an inlet adapted for connection to the low pressure side of a refrigerant circulating system; means co-acting with one of said heads adapted to secure the casing of an electric motor thereto; a cover secured to the other of said heads and co-acting therewith to provide a high pressure chamber having an outlet adapted to be connected to the high pressure side of the refrigerant circulating system; a third head in said high pressure chamber; a plurality of segmental stator elements between said other and the third said heads and having attaching flanges at their ends; fastening members co-acting with said flanges to secure the stator elements to said other and third heads a predetermined angular distance apart; said stator elements having internal arcuate working surfaces; a rotatably mounted drive shaft adapted to be operatively connected to said motor and passing through said heads; said shaft having a cam between said other and third heads eccentrically related to the shaft axis; a piston mounted on said cam and having peripheral working surfaces; vanes slidably mounted in said stator elements and spring-urged into engagement with said working surfaces of the piston for co-action therewith and with the working surfaces of the stator elements in defining working chambers; means co-acting With the piston to prevent its rotation and to compel oscillation of the piston through a predetermined angular distance when the piston is driven by the cam; said other head having intake ports communicating'with said low pressure chamber and with said working chambers so as to be controlled by an end wall of the piston; the third said head having exhaust ports communicating with said high pressure chamber and with said working chambers so as to be controlled by the other end wall of the piston; said intake and exhaust ports being located in the working chambers for the piston to co-act therewith in creating a partial vacuum therein, then admitting refrigerant to the working chambers through the intake ports, followed by compression of the refrigerant and its discharge through the exhaust ports; and means co-; acting with the exhaust ports to enable compressed refrigerant to be pumped into the high pressure chamber.

References Cited by the Examiner UNITED STATES PATENTS 1,983,997 12/1934 Rolaff 230-149 2,073,101 3/1937 Fox 91-56 2,159,936 5/1939 Smith 230-147 2,175,913 10/1939 Philipp 230-147 2,193,250 3/1940 Hull et al. 230-147 2,195,835 4/1940 Bilderbeck 230-147 2,476,383 7/1949 Porteous 230-147 2,732,126 1/1956 Smith 230-149 2,992,769 7/1961 Manzanera 230-147 MARK NEWMAN, Primary Examiner. 

1. IN A HIGH PRESSURE AND TEMPERATURE REFRIGERANT VAPOR COMPRESSOR, A HOUSING DEFINING A HIGH PRESSURE CHAMBER HAVING AN OUTLET ADAPTED FOR CONNECTION TO THE HIGH PRESSURE SIDE OF A REFRIGERANT CIRCULATING SYSTEM AND PROVIDED WITH A HEAD; A SECOND HEAD IN SAID CHAMBER; A PLURALITY OF SEGMENTAL STATOR ELEMENTS BETWEEN SAID HEADS HAVING INTERNAL ARCUATE WORKING SURFACE; MEANS RIGIDLY SECURING THE STATOR ELEMENTS TO THE HEADS A PREDETERMINED ANGULAR DISTANCE APART; A ROTATABLY MOUNTED DRIVE SHAFT IN SAID HOUSING HAVING A CAM BETWEEN SAID HEADS ECCENTRICALLY RELATED TO THE SHAFT AXIS; A PISTON MOUNTED ON SAID CAM HAVING PERIPHERAL WORKING SURFACES; VANES SLIDABLY MOUNTED IN SAID STATOR ELEMENTS AND SPRING-URGED INTO ENGAGEMENT WITH SAID WORKING SURFACES OF THE PISTON FOR CO-ACTION THEREWITH AND WITH SAID WORKING SURFACES OF THE STATOR ELEMENTS IN DEFINING WORKING CHAMBERS; MEANS CO-ACTING WITH THE PISTON TO PREVENT ITS ROTATION AND COMPELLING OSCILLATION OF THE PISTON THROUGH A PREDETERMINED ANGULAR DISTANCE WHEN THE PISTON IS DRIVEN BY THE CAM; THE FIRST SAID HEAD HAVING INTAKE PORTS ADAPTED FOR CONNECTION TO THE LOW PRESSURE SIDE OF THE REFRIGERANT CIRCULATING SYSTEM AND COMMUNICATING WITH SAID WORKING CHAMBERS SO AS TO BE CONTROLLED BY AN END WALL OF THE PISTON; THE SECOND SAID HEAD HAVING EXHAUST PORTS COMMUNICATING WITH SAID HIGH PRESSURE CHAMBER AND WITH SAID WORKING CHAMBERS SO AS TO BE CONTROLLED BY THE OTHER END WALL OF THE PISTON; SAID INTAKE AND EXHAUST PORTS BEING LOCATED IN THE WORKING CHAMBERS FOR THE PISTON TO CO-ACT THEREWITH IN CREATING A PARTIAL VACUUM THEREIN, THEN ADMITTING REFRIGERANT TO THE WORKING CHAMBERS, FOLLOWED BY COMPRESSION OF THE REFRIGERANT AND ITS DISCHARGE FROM THE WORKING CHAMBERS; AND MEANS CO-ACTING WITH THE EXHAUST PORT TO ENABLE THE COMPRESSED REFRIGERANT TO BE PUMPED INTO THE HIGH PRESSURE CHAMBER. 